Last updated: March 17, 2025
September in Castlerock, United Kingdom, presents a mild and often damp transition from summer to autumn. With maximum temperatures reaching 17°C (64°F) and an average of 14°C (57°F), the weather remains comfortable for outdoor activities. However, the minimum temperature drops to 9°C (49°F), reminding residents of the season's shift. Rainfall is notable this month, with 117 mm (4.6 in) of precipitation spread across 20 days, resulting in a high humidity level of 88%. Nature comes alive with rich colors as Castlerock embraces the cooler, wetter days of September.
As September rolls into Castlerock, the temperatures begin to subtly shift, heralding the onset of autumn. With a minimum of 9°C (49°F) and an average of 14°C (57°F), the warmth of summer gradually gives way to cooler days. Highs reach a comfortable 17°C (64°F), making it a pleasant time for outdoor activities before the chill of October sets in. This transition is marked by a slight increase in morning mists and the rustle of leaves, capturing the essence of the changing season. With September's blend of mild warmth and cool breezes, it's the perfect opportunity to enjoy the natural beauty of the area before winter approaches.
September in Castlerock sees an average precipitation of 117 mm (4.6 in), making it one of the wetter months of the year, alongside August, which recorded 146 mm (5.7 in). This month is marked by an increase in rainy days, with a total of 20 days of precipitation, a trend that reflects the transition into autumn, where frequent showers are more common. Interestingly, while September's rainfall is less than August's, it hints at a gradual increase leading into October's spike at 161 mm (6.3 in). This pattern underscores a shift from summer's milder conditions to the more robust rains typical of the fall season, inviting both the lushness of the landscape and the inevitable challenges posed by persistent wet weather.
As summer fades into autumn, September in Castlerock, United Kingdom, brings a noticeable uptick in humidity, reaching 88%—the highest level since January. This increase marks a significant contrast from the lower levels observed during the late spring and early summer months, where humidity dipped to 82% in May. Throughout the year, the humidity levels remain relatively high, fluctuating between 82% and 90%, but September's swell serves as a precursor to the even more humid conditions of October and November. As the days begin to shorten and the air cools, residents can expect a muggy transition into autumn, setting the stage for the wetter months ahead.
As summer transitions into autumn, September in Castlerock, United Kingdom sees a UV Index of 5, placing it in the moderate exposure category. This marks a slight decrease from the height of summer, when UV levels peaked at 8 during June and July, necessitating caution with a quick burn time of just 15 minutes. In contrast, the moderate levels in September allow for a more leisurely 30-minute burn time, encouraging outdoor activities while still reminding residents to safeguard their skin against potential sun damage. As we move towards cooler months, awareness of changing UV patterns can help ensure sun safety throughout the year. For more information, check out the detailed Castlerock UV Index.
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As summer transitions into autumn in Castlerock, September shines with a robust 283 hours of sunshine, maintaining a delightful glow before the colder months settle in. This month, while less sunny than the peak of July with its impressive 404 hours, still offers a significant amount of light compared to the dim winters ahead. The gradual decline from the sun-soaked heights of late spring and early summer is evident, yet September stands out as a vibrant bridge, ensuring that nature’s warmth lingers just a bit longer. With each passing month, the hours of sunshine shrink dramatically, highlighting September as a precious time to bask in the golden rays before they wane into the shorter days of October and beyond.
In Castlerock, United Kingdom, the likelihood of sunny weather in September hovers around a modest 23%, aligning closely with the sunnier months of January and July. As summer winds down, this percentage reflects a slight dip from the warmer months of April and May, which boast considerably higher chances of sunshine at 43% and 36% respectively. However, September's sun chances remain more favorable than the dreary depths of winter, where the likelihood falls to around 14% to 16%. This pattern suggests that while September may not offer the peak sun of summer, it still provides a welcome respite before the seasonal shift into cooler, cloudier days.
As summer fades, September in Castlerock, United Kingdom, welcomes a gentle decline in daylight, averaging 12 hours compared to the sun-soaked 16 hours in May and June. This transitional month marks a shift from the vibrant, long days of summer, gradually easing into autumn's embrace. Following August’s ample 14 hours of light, September's clock continues to tick down, hinting at the impending shorter days of fall, with October dropping to 10 hours. The steady rhythm of daylight duration not only frames the changing seasons but sets the stage for the cozy evenings ahead, inviting residents to savor the soft glow of autumn in this picturesque coastal town.
As September unfolds in Castlerock, the wind begins to pick up its gentle pace, averaging 5.5 m/s (12 mph)—a subtle increase from the calmer summer months. This September breeze serves as a transition from the lazy warmth of July and August, where winds hovered at their lowest, to the more invigorating gusts seen in the approaching autumn. Historically, September's winds are moderate compared to the year’s peak in winter and early spring, but they herald the arrival of change, setting the stage for the brisker months ahead. The gradual escalation from the serene summer to the lively autumn winds showcases Castlerock's dynamic coastal climate, where each season gifts its unique breath of air.
The weather in Castlerock changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of September's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Castlerock and find detailed weather information for every month.
In comparing the weather of September and January, we see notable differences in temperatures and overall conditions. September features a milder climate, with minimum temperatures around 9°C (49°F) and average highs reaching 17°C (64°F), accompanied by relatively high humidity at 88%. In contrast, January experiences cooler temperatures, with lows dropping to 2°C (36°F) and average highs only reaching 13°C (56°F). Precipitation levels are quite similar, with September receiving 117 mm (4.6 in) over 20 days and January slightly lower at 109 mm (4.3 in) over 17 days. For a detailed look at January weather, you can check Castlerock weather in January.
When comparing the weather in September and February, September tends to be milder with an average temperature of 14°C (57°F), while February is significantly colder, with an average of only 7°C (44°F). September experiences slightly less precipitation, at 117 mm (4.6 in) over 20 days, compared to February's 132 mm (5.2 in) across 18 days. Both months have high humidity levels, but September is marginally more humid at 88% versus February's 86%. Overall, September offers a more temperate climate, making it feel more comfortable than the chillier February weather. For more information, you can check Castlerock weather in February.
In comparing the weather between September and March, we see notable differences in temperature and overall conditions. September enjoys milder temperatures, with an average of 14°C (57°F) and highs reaching 17°C (64°F), while March presents a chillier atmosphere, averaging only 7°C (45°F) with a maximum of 12°C (54°F) and even dipping to a minimum of -1°C (31°F). Both months experience significant precipitation, with September receiving 117 mm (4.6 in) over 20 days and March slightly less at 112 mm (4.4 in) over 18 days. Humidity levels are also comparable, with September at 88% and March at 86%. For more detailed insights into March’s climate, you can check the Castlerock weather in March.
When comparing the weather between September and April, notable differences arise in both temperature and precipitation. September typically experiences milder temperatures with a minimum of 9°C (49°F) and an average of 14°C (57°F), while April is cooler, with a minimum of 2°C (36°F) and an average of 8°C (47°F). Additionally, September sees higher precipitation levels, measuring 117 mm (4.6 in) over approximately 20 days, compared to April's 55 mm (2.2 in) spread across only 12 days. Humidity levels are relatively similar, with September at 88% and April at 85%. For more detailed insights on April's weather, visit Castlerock weather in April.
When comparing the weather in September and May, September tends to be slightly warmer, with average temperatures around 14°C (57°F) compared to May's 10°C (50°F). September also experiences more rainfall, averaging 117 mm (4.6 in) over 20 days, while May sees less precipitation at 72 mm (2.9 in) across 13 days. Additionally, September has a higher humidity level at 88%, compared to May's 82%. For more detailed weather information in May, you can visit Castlerock weather in May.
In September, the weather is slightly warmer with an average temperature of 14°C (57°F), compared to June's average of 12°C (54°F). Both months experience similar maximum temperatures, peaking at 17°C (64°F). However, September tends to be wetter, with 117 mm (4.6 in) of precipitation over 20 days, while June sees 105 mm (4.1 in) of rain over 17 days. Additionally, September holds higher humidity levels at 88%, compared to June's 84%. For more detailed information on June weather patterns, you can refer to Castlerock weather in June.
In comparing the weather between September and July, September showcases slightly cooler temperatures, ranging from a minimum of 9°C (49°F) to a maximum of 17°C (64°F), while July typically experiences milder conditions with temperatures ranging from 11°C (52°F) to 19°C (67°F). Precipitation levels are comparable, with September receiving 117 mm (4.6 in) over 20 days, slightly more than July's 110 mm (4.3 in) over 17 days. Humidity is also marginally higher in September at 88%, compared to July's 86%. For further details about July weather, you can check out Castlerock weather in July.
Comparing the weather in September to that of August reveals some notable differences. September experiences slightly cooler temperatures, with a minimum of 9°C (49°F) and a maximum of 17°C (64°F), while August has a minimum of 11°C (52°F) and a maximum of 18°C (66°F). Precipitation levels are also higher in August, with 146 mm (5.7 in) compared to September's 117 mm (4.6 in), although both months see precipitation on about 20 days. Humidity levels are quite similar, with September at 88% and August at 86%. For more detailed information, you can visit Castlerock weather in August.
September and October present a noticeable shift in weather patterns. In September, the temperatures range from a minimum of 9°C (49°F) to a maximum of 17°C (64°F), with an average of 14°C (57°F). The month experiences significant precipitation, totaling 117 mm (4.6 in) across about 20 days, accompanied by high humidity levels at 88%. In contrast, October sees a slight dip in temperatures, with a minimum of 5°C (42°F) and averaging at 12°C (53°F), reaching a maximum of 16°C (62°F). Precipitation increases to 161 mm (6.3 in) spread over 24 days, while humidity remains comparable at 89%. For more detailed insights into October weather, you can check out Castlerock weather in October.
In comparing the weather of September and November, notable differences can be observed in temperature and precipitation. September typically sees a milder average temperature of around 14°C (57°F), with maximums reaching 17°C (64°F). In contrast, November experiences a drop in average temperature to just 9°C (49°F), with maximums peaking at 14°C (58°F). Additionally, November tends to be wetter, with an average precipitation of 156 mm (6.2 in) spread over 23 days, compared to September's 117 mm (4.6 in) over 20 days. Humidity levels are slightly higher in November at 90%, compared to September's 88%. For more detailed information about weather specifics, you can check Castlerock weather in November.
September and December exhibit notable differences in weather conditions. In September, temperatures range from a minimum of 9°C (49°F) to a maximum of 17°C (64°F), with an average of 14°C (57°F). The month sees a substantial amount of rainfall, totaling 117 mm (4.6 in) over 20 days, while the humidity remains high at 88%. In contrast, December experiences cooler temperatures, with a minimum of 2°C (35°F) and a maximum of 12°C (54°F), resulting in an average of 8°C (46°F). This winter month is also wetter, with 166 mm (6.5 in) of precipitation recorded over 23 days, but the humidity dips slightly to 86%. For more detailed insights into December's weather, visit Castlerock weather in December.
As September unfolds in Castlerock, the weather takes on a unique character, transitioning from the warmth of summer to the cool embrace of autumn. This month typically brings mild temperatures paired with noticeable humidity, creating a fresh atmosphere that's both invigorating and slightly damp. With an increase in precipitation days, you might find the skies weeping more often, but this just adds to the lush scenery that epitomizes the region’s charm. The contrast of warm afternoons and cool evenings invites locals and visitors alike to embrace outdoor activities while appreciating the subtle shifts in nature. To explore the nuanced patterns of Castlerock’s climate year-round, visit Castlerock Climate.